Published: Sunday, July 21, 2013 at 10:00 a.m.

Last Modified: Friday, July 19, 2013 at 2:40 p.m.

The story may or may not be true, but "The Conjuring," the latest Hollywood tale of demonic possession, has an air of authenticity, thanks in part to one local theology expert.

The film follows the investigation of a haunting at a Rhode Island farmhouse where the Perron family, led by parents Carolyn and Roger Perron (Lili Taylor and Ron Livingston), lived in the 1970s.

As Carolyn is gradually taken over by a spirit that drives her to kill, paranormal investigators the Warrens – Ed, a demonologist, and Lorraine, a trance medium – step in to help. The couple (played by Patrick Wilson and Vera Farmiga) rely on Lorriane's clairvoyant abilities and traditional Roman Catholic exorcism rites to rid the family of its demons.

"I was totally blown away that everyone got the theology of Catholicism exactly right," said Diana Pasulka, a UNCW associate religion professor hired as a history and language consultant on the film. "As a consultant, you have no idea if they're going to do what you're telling them or not. In this case, every time you hear Latin spoken in the movie, I helped with the translation."

Pasulka just so happens to be writing a book on the doctrine of Purgatory and the medieval Latin Church. The Latin that audiences will hear during a flashback to an earlier exorcism and in a pivotal scene at the haunted house features a kind of Latin that dates to the Middle Ages.

Pasulka can read and speak medieval Latin, but can't pronounce the words exactly, she said.

She and the film's writers, Chad and Carey Hayes, recruited one of her former UNCW students, Chris Moreland, now in graduate school at the University of California Berkeley, to help.

"The last scene is tough. I anticipated problems with actors being able to recite the verses from the ‘Rituale Romanum' (one of the Roman Rites) and Patrick (Wilson) was having a bit of a hard time remembering the verse," Pasulka said. "When I finally saw the movie, I could not believe how eloquent it was."

The professor, a mother of five who has worked at UNCW for 11 years, said she initially resisted working on the film because she thought it might sensationalize the Warrens' experiences.

She's also a believer.

"I didn't want to be involved in any projects that are gratuitously evil or violent, but Chad and Carey wrote a positive story and were adamant that good would triumph over evil," Pasulka said. "When I was at set and watching some of the scenes, I was terrified, but when I saw the movie, I only have really good feelings when I look back now. I think a lot of people who are religious will respond to the message."